Diazotype compositions containing



Patented May 20, 1952 UNITED STATES PATENT OFFICE DIAZOTYPE COMPOSITIONS CONTAINING UNSATURATED ALKYL N-DERIVATIVES OF AMINO DIAZOS No Drawing. Application December 29, 1948, Serial No. 68,072

Claims. 1

This invention relates to the production of diazotype light sensitive layers or diazotype materials and more particularly to diazotype materials wherein the light sensitive agent is a diazo derivative of an aromatic p-diamine.

The diazotype process, as is well known, involves the treating of a carrier or base, usually paper which may be either opaque or transparentized, or film of the cellulose ester or cellulose ether type, with a sensitizing composition containing a diazo compound as the light sensitive element. This treated base is exposed to actinic light through a pattern and a positive reproduction of the original obtained by development of the undecomposed diazo compound under the protected portions of the pattern, by means of alkaline coupling with an azo dye coupling component. The azo'dye coupling component used for development of the image may be contained in an alkaline developing solution, as is the case in the so-called wet development or one-component process. In the dry development or two-component diazotype process, the sensitizing composition with which the base material is treated contains both the diazo compound and the azo coupling component. Here, the azo dye image is formed after exposure of the sensitized material by subjecting the exposed material to the action of alkaline vapors such as ammonia vapors. The diazotype photosensitive material for the two-component process must have good stability against precoupling, so that the sensitized layers may be stored for reasonable periods of time under average conditions of temperature and humidity prior to use.

The two-component diazotype process is extensively used for the preparation of intermediate or transition prints in cases where it is desired to make a large number of reproductions. By making such an intermediate diazotype transition print it is only necessary to expose the original once or a few times since the transition print is thereafter used to make the desired number of duplicates. Consequently, a valuable original drawing may be spared the rigorous treatment of repeated exposures which might result in the impairment of even destruction of the original drawing. In producing an intermediate diazotype print, a transparent or semitransparent paper or film is coated with a light sensitive diazotype sensitizing solution and dried. It is then exposed to actinic light rays, particularly from a source rich in the ultraviolet band of from 3600 A. to 4200 A. under the drawing or picture to be reproduced. The image is then developed by contacting the exposed light sensitive surface, if it be a two-component diazotype, to ammonia vapors.

The efiiciency of transition prints depends upon the covering power'or photographic density of the azo dye imageproduced and particularly its opacity to ultraviolet light, and also upon the transparency of the background surrounding the developed pattern. The clarity of the background, and hence its transparency, is decreased if color has been produced therein due to the residual or undecomposed diazo compound, or to premature coupling of the dye components prior to use. Such casual color in the background of the intermediate print will be reproduced in subsequent copies due to the ultraviolet absorbing qualities of the transition color.

The efliciency of transition prints also to some extent depends upon the depth or visual density of the image produced. Light colored images of poor visual density which may satisfy the requirements of opacity to ultraviolet light and ability to resist precoupling nevertheless have the disadvantage of rendering difficult the detection of flaws in the intermediate image, and it is often necessary to make a test print from the transition print of a deep contrast before such flaws can be detected, with consequent loss of time, convenience and economy.

We have now found that a new class of diazo compounds which are derived by mono diazotization of a p-phenylene diamine containing at least one unsaturated lower alkyl substituent on the undiazotized amino group give excellent results when used as the light sensitive agents of a diazotype layer. This new class of diazo compounds may be used with coupling components which will produce dye images'in dark shades such as blues or those which will produce ultraviolet light absorbing shades such as sepia for use in diazotype transition printing. The

amines from which the diazo compounds of this class are derived have the formula N-allylamino-p-benzene diazonium chloride N-methallylamino-p-benzene diazonium chloride N-methyl-N-(2-hydroxy 3 butenyDamino-pbenzene diazonium chloride N-hydroxyethyl-N- (2-hydroxy-"3 -butenyl) amino-p-benzene diazonium chloride diazonium N,N-di(2-hydroxy-3sbutenyl) -aminop -benzene diazonium chloride N-cyclohexyl N(2hydroxy- 3 -butenyl)aminop-benzene diazonium chloride 'N-methyl-N-butadienyl-amino p benzene diazonium chloride It has been found that diazo compounds of this class when employed with one of the azo components generally used for diazotype work either by the dry development process wherein the diazo compound and coupling component are both con tained in the light sensitive layer or by the wet development process wherein only the diazo com-'- pound is contained in the light-sensitive layer and the azo component is applied aspart of an alkaline developingsolution, reproductions can be obtainedhav-ingimages of'bright dark tones I andthe azo coupling component are incorporated in a two-component system for the dry developingdiazotype process. By reason of the fact that they decompose completelyand readily upon exposure to light, particularly the actinic rays of ultraviolet light, the diazo compounds of this class are characterized by an excellent printing speed whenused either in a two-component or onecomponent diazotype system. When used in conjunction with'the proper azo components such as resorcinol and resorcinol derivatives these dlazoswill produce the image in a sepia shade which has excellent photographic density or opacity to ultraviolet light. These sepia reproductions having a very high degree of opacity will yieldclear-and sharply defined copies-in the final print when applied to diazotype transition print- The intermediate sepia reproductions-will not-'blur'or ofisetwhen the printis used as a mask."

Thedia'zo compounds of this class maybe prepared by one of several methods. be pr'epa-r'ed by reactingunsaturated alkyl halides; such allyliodide and methallyliodide with aromatic amines such as aniline, N-methyl-- alline, o-toluidine, N-hydroxyethyl-o-toluidineand the like. The reaction product'of the alkyl halide and the aromatic amine is then nitrosated, reduced, diazotized and stabilized in the usual manner. In orderto prepare those derivatives which contain a hydroxy group in addition to an unsaturated group in the N-substituent or substituents, the aryl amines are reacted with an unsaturated alkylene oxide, such as 3,4-epoxy-1-butene. The reaction product is then nitrosated, reduced, diazotized and stabilized in the same manner as above.

The diazotype layers produced from-thisclass of diazo-compounds may be effected in theusualmanner, wherein the base or support carrying-or containing the light sensitive compounds, the azo components and other coating materials is coated, dipped, brushed or sprayed with the sensitizlng solution, the particular type of application generally depending upon the character of the carrier employed. As carriers, such materials as paper or cloth which may be opaque, semi-transparent or of a transparentizedtype film such as prepared-from cellulose nitrate, cellulose acetate; or cellulose es'ters; Ire'generat'ed' cellulose. superpolymers and": polymerization They may 4 products; ceramic plates or sheet metal may be employed. Where paper is used as the base or support for the light sensitive coating, the coated solution is generally applied by using a trough and doctor blade but may, if desired, be brushed or sprayed. When a film or spirit soluble plastic is used as a support swelling agents should be added to the coating solution in order to obtain proper-penetration and the solution is generally applied by a dipping method.

In addition to the diazo compound, azo component and such swelling agents as may be added, the coated solution may contain the usual adjuncts such as metal" salts designed to intensify .the dye image and increase its water resistance, such as aluminum sulfate, titanium ammonium fluoride and nickel sulfate; stabilizing agents such as' thiourea, thiosinamine andnaphthalenetrisulfonic acid; acids designe'd'to' retard precoupling,.such as citric acid, tartaric acid and boric acid; and hygroscopic agents such as glycol, glycerine and dextrin to'protect' the light sensitive layer from excess moisture.

Whensingle' component diazotype layers are desired the coating methods for producing the light sensitive layer on the desired support are the same as employed for the production of twocomponent diazotype layers except that the azo component is omitted from the coating solution as previously pointed out and as is well known The azo component is then added to the alkaline developing solution. As will be obvious adjuncts added to the coating solution to improve its precoupling properties will be unin the art.

necessary in the case of one-component solutions.

As coupling components for either the onecomponent or two-component di'a'zotype" sys tems we may use any azo coupling component known to be suitable for diazotype light sensitive As examples of these there may be men'- layers. tioned (1) 2,3-dihydroxy'naphthalene and'its sulfonic methyl-S-hydrox-y naphthalene and 1 its reaction product with formaldehyde-hi methylamine (6) Hydroxynaphtho -imidazoles,- such as '7=hydroxynaphtho=l,2:4,5 imidazole:

Z-carbethoxy 7' hydroxynaphtho-1,-

2'-:4,5-imidazole- (7) Phenol and phenol derivatives- (8) Cresols (9-) Resorcinol and resorcinol derivatives, such 4-chlorore'sorcinol Dichlorore'sorcinol Resorcinol esters and ethers,

Some 'of these'azo components; notably those' oi: the resorcinol family which will'produce sepia:

images have a fast coupling rate. This-tends to impair the precoupling stability of a two-'component system containing such an azo component.

Since it'is desirable to use these azo components which will produce sepia; shades in the produc= tlon' 'oi diazotype transparencies;precoupling in-= bility and this background color will absorb.

actinic light in areas where the transparencies should transmit light. Although some of the azo coupling components which producesepia images are more stable than others this disadvantage which is inherent in the class of am components which produce the ultraviolet absorbing shades is modified or overcome when using the diazo compounds of this invention. 1 a The following examples will serve to illustrat further the preparation of diazotype photoprinting materials from the diazo compounds'of our invention and it being understood that the invention is not limited to the particular materials or preparations therein described. Unless otherwise specified, the parts are by weight.

EXAMPLE 1 Transparentized paper is coated with a coating solution containing the following materials per 100 parts of water:

3.2 parts N allylamino p benzene diazonium chloride CdClz double salt 1.8 parts resorcinol 8.0 parts citric acid 4.0 parts thiourea The thus coated transparentized paper is then dried and exposed to light under a pattern and the print developed by drying the exposed diazotype coated paper through ammonia fumes. The sepia colored positive reproduction is obtained on a clear background. The opacity to ultraviolet light of the developed image is outstanding. Visual appearance, wash and light-fastness and fastness to offset are also good. This sepia dye reproduction may, therefore, be used as a positive original with ordinary diazotype reproduction media or other light sensitive reproduction media to yield excellent reproductions in any desired color. Its printing speed during exposure is excellent and its resistance to precoupling prior to exposure is also very satisfactory.

EXAMPLE 2 Transparentized paper is coated with a solution containing the following materials per 100 parts of water:

3.5 parts N-methyl-N-methallylamino-p-benzene diazonium chloride-ZnClz double salt 2.! parts 4,6-dichlororesorcinol 8.0 parts citric acid 4.0 parts thiourea 3.0 parts isopropanol The thus coated paper is dried in the usual manner. It has excellent precoupling stability and can be stored for long periods of time without any noticeable spontaneous formation of color due to coupling of the dye components. When exposed to the actinic rays of ultraviolet light under a positive original and developed with ammonia vapor this coated transparency produces a well defined sepia colored positive reproduction of the original on a clear background. The opacity of the sepia colored image and its ability to thus absorb ultraviolet rays in the colored areas so as to prevent printing through in those areas is outstanding. The visual appearance, wash and light fastness and fastness to oilset of the sepia colored image are also good. As in Example 1, the product of this example may be used in transition printing thus, the sepia colored image derived from the positive original by exposure and development may be employed inplace of the original for printing through on the ordinary diazotype reproduction media or other photo-printing reproduction media for the purpose of producing additional reproductions desired color.

EXAMPLE 3 Transparentized paper is coated with a solution containing the following materialsper parts of water:

The thus coated paper is dried in theusual manner and is found to have excellent stability against precoupling during storage and when exposed to ultraviolet light under a positive original and developed with ammonia vapor it produces a well defined sepia colored image which is a positive reproduction of the original on a clear background. The opacity of this'image to ultraviolet light is outstanding. Its visual appearance, wash and light fastness and fastness to offsetare also good. This sepia dye reproduction image may, therefore, be used in place of the positive original for the production of further copies by printing through on to ordinary diazotype reproduction media or other photo-printing media to yield excellent reproductions in any desired color.

EXAMPLE 4 Diazotype paper stock is coated with a solution containing the following material per 100 parts of water:

2.4 parts N-hydroxyethyl-N-(2-hydroxy-3-butenyD-amino-p-benzene diazonium chloride- ZnClz double salt 1.5 parts 2,3-dihydroxynaphthalene-6-sulfonic acid 8.0 parts citric acid 4.0 parts thiourea 5.0 parts isopropanol of the dye components.

EXAMPLE 5 Transparentized paper is coated with a coating solution containing the following material per 100 parts of water:

3.6 parts N -phenylN-allylamino=p-benzene diazonium chloride ZnCla double salt 2.6 parts resorcinoll-sulfonicacid 8.0 parts citric acid 4.0 parts thiourea 5.0 cc. isopropanol The thus coated transparency is dried in the usual manner and is found to have excellent precoupling stability. When exposed to ultraviolet light under a positive original and developed with ammonia vapor a sepia colored positive reproduction of the original on a clear background is obof any The" opacity 0F ='the' "sepla; imegeor"-itsa=- abflity-m absorb"eultralvlolefi light'emanatlons is outstanding; Its-' vlsual =appearance; -wash= and light l'alstness andffastness to'ofiset are also good; This Mpiwdye reproduction iimage may ibe" used"- as a positive original with ordinary diazotypere-'iproduction media. or othr pl i'oto-printing media. to gleld excellent reproductions in any desired coTofi-i Transparentized paper is poa ted with a coating solu'tlh containing tfi'e renewing m'aterialpz" 100 pe'ft''fif water 3.6 parts N,N-di(2-hydroxy-3*-butenyl) amino 15 p-benzene diazonlum chlorlde znCl-zdouble'salt 1.8 parts resorcinol 8.0 parts citric acid 4.!) parts thlourea 1 5.llscc;--isbprdiianol 20 The-mus moatedtrafisparenoy is dried. in "the usubl'm'anfini It is foundtohaveexc'e'llent bre coupling stability and when 'exposed'to the actinic raysM ultravlolet-lightunder 1 a positive original I and developed' witlr ammonia vapor a sepia colored positive reproduction of the originalon'e clear ba'ckground 'is obtained. The opacity bf-the' lmageimr its :ability to=- absorb" ultraviolet light" emmatlonsi'is outstandingz Its-"visual appear Tdbles'of structural formulae I. BASES FdRDIltZO DERIVATIVES ancefwesl'i en'd light fdstness end msmese' w orrseearemsa goods" In view ofthe exceuent r coupling stability-or theunexposecr llghfi'sensltlve coating and the outstanding opacity of 'the image produced byexposur'e and 'developninmhls pied uct ls emlnently suited for"di'ezdtyp'ewransltlorr prlntlng.=ia.nd TwhenuseTes an 'lntefliiedlate bosi tive original 11; will produce excellenfreprodiic -f tions on ordinary diazotype repioducfiion edia The thus coated paper iS tlried' in-tIie usilhl manner. Upon exposing it undl e'pett'er and developed in a, mildly alkaline soll'itioncontiining resorcinol excellent sepia colordprln6s"bna clear background are obtained;

Compound l -N-all laminoaniline: P y HAL (2) p-N-ma'lliy]-N-metlmllylamlnormlllne;.

Structural rorniun a p-N-N-dl(2-hydroxy-flwuiexiyhimlno aniline l Caron-013 0113 II. DIAZONIU M SALTS Compound Structural Formula (1) N-sllylamino-prbenzene diazo- NIL-C Hr-CH=C Ha nium chloride 'CdOl, double salt N=NL3Cd0l1 (2) N-methyl-N-methallylamlno- CH; p-benzene: diazonlum chlo- 7} ride ZnCl double salt N\ 1 cm-c=om N==NCL%ZnCh 3 N- methyl-N- (2 -hydroxy-3- CH: butenyl) -amino-p-benzine diazoiiiurrlit chloride ZnCl I 4\ doub e S CHs-CHCH=CH:

=NCL9ZnCh (4) N-hydroxyetliyl-N-(2-hydroxy- GH -C H OH B-DutenyD-amlno-p-benzene N/ chloride 211011 s on e v CHrCH-CH=CHo N=NCLZnClg o) N-phenyl-N-allylamino-pbenzene diazonium chloride ZnCl; double salt amlno-p-benzone diazonium chloride ZnOl; double salt Ha Ha H C-C We claim:

1. Diazotype materials comprising a base having a photosensitive coating which includes a light sensitive mono diazo derivative of an aromatic p-diamine of the benzene series having the following formula wherein R1 is a member of the group consisting of alkyl radicals of less than five carbon atoms containing at least one unsaturated carbon to carbon linkage and such radicals containing a hydroxyl group and R2 is a member of the group consisting of hydrogen, alkyl, hydroxyalkyl, aryl, cycloaliphatic and R1 radicals.

2. Diazotype materials comprising a base having a photosensitive coating which includes a light sensitive mono diazo derivative of an aromatic p-diamine of the benzene series having the formula wherein R1 is a member of the group consisting of alkyl radicals of less than five carbon atoms containing at least one unsaturated carbon to carbon linkage and such radicals containing a hydroxyl group and R2 is a member of the group consisting of hydrogen, alkyl, hydroxyalkyl, aryl, cycloaliphatic and R1 radicals and an azo dye coupling component.

3. A diazotype material comprising a base having a photosensitive coating which includes a light sensitive mono diazo derivative of p-N-allylaminoaniline and an azo dye coupling component.

4. A diazotype material comprising a base having a photosensitive coating which includes a light sensitive mono diazo derivative of p-N- methyl-N-methallylamino aniline and an azo dye coupling component.

5. A diazotype material comprising a base having a photosensitive coating which includes a light sensitive mono diazo derivative of p-N- methyl N(2 hydroxy-3-butenyl)aminoaniline and an azo dye coupling component.

WILLIAM H. VON GLAHN. LESTER N. STANLEY.

REFERENCES CITED The following references are of record in the tile 01' this patent:

UNITED STATES PATENTS Number Name Date 1,870,930 Sprongerts et al Aug. 9, 1932 2,397,927 Dickey et al Apr. 9, 1946 

1. DIAZOTYPE MATERIALS COMPRISING A BASE HAVING A PHOTOSENSITIVE COATING WHICH INCLUDES A LIGHT SENSITIVE MONO DIAZO DERIVATIVE OF AN AROMATIC P-DIAMINE OF THE BENZENE SERIES HAVING THE FOLLOWING FORMULA 